At present, the organic electroluminescent display and organic light emitting diode (OLED) have gradually become the mainstream of the display field due to their excellent performance of low power consumption, high color saturation, wide visual angle, small thickness, and flexibility. The OLED can be classified into bottom-emitting type and top-emitting type according to the light emission manner. The light emission in the bottom-emitting OLED comes from the side of the substrate, while the light emission in the top-emitting OLED comes from the top.
In order to realize full color of the large-size OLED panel, top-emitting white organic light emitting diodes and a color filter layer are generally superimposed. In the prior art, when the top-emitting OLED panel is manufactured, as shown in FIG. 1, a layer of white organic light emitting diodes 02 is formed on a substrate 01 firstly, then a thin film encapsulation layer 03 is formed with the thin film encapsulation technology. The thin film encapsulation layer 03 is a multi-layer film structure of at least three layers constituted by mutual alternation of an inorganic thin film layer 031 and an organic thin film layer 032, for blocking permeation of external moisture and oxygen. The inorganic thin film layer 031 has a relatively high compactness and is the main water and oxygen barrier layer; however, the inorganic thin film layer 031 has a relatively low elasticity, and a large inner stress, which is easily affected by the external force so as to generate cracks or to be stripped from the OLED device. Hence, it should cooperate with the organic thin film layer 032, which is formed by using the methods such as monomer deposition or polymer coating as a buffer layer. The organic thin film layer 032 has a relatively high elasticity, which can effectively prevent the inorganic thin film layer 031 from cracking. After the thin film encapsulation layer 03 is formed with the thin film encapsulation technology, a color filter layer 04 comprising filters of at least three colors should also be formed on the thin film encapsulation layer 03. The color filter layer 04 is used for realizing filtering of various colors. However, the OLED panel formed in this way has a relatively thick film layer. The manufacturing process is relatively complex; moreover, the light path is increased, the luminous efficiency is reduced, and the display effect of the OLED panel is influenced.
Therefore, how to simplify the film layer structure of the OLED panel, reduce the manufacturing processes, shorten the light path, and improve the luminous efficiency is a technical problem that needs to be solved by the skilled person in the art urgently.